Two major baseball collections will feature in Heritage Auctions' online sports sale that will run from May 15-17.
The Ernie Schworck Collection of Milestone Baseballs and The Charlie McCabe Collection of LeRoy Neiman Original Baseball Art are likely to prove a big draw for collectors.
Schwork was a photographer for UPI during the 1960s and covered a range of sporting events.
His collection consists of a range of important balls from across the sport's history, including the Sandy Koufax ball from the August 1, 1959 game against the San Francisco Giants at Chavez Ravine, when he struck out 18 batters (valued in excess of $20,000).
Another Koufax ball from his 1963 no-hitter carries an identical estimate.
Chris Ivy, director of sports auctions at Heritage, commented: "His photography is instantly recognizable to anybody who was reading the sports pages in the 1960s.
"With his proximity to great players and great moments, Ernie had the chance to acquire some very important game-used baseballs and to, unknowingly perhaps, build a world-class collection. These momentous balls were kept in his desk drawer for years."
The McCabe collection consists of work painted on baseballs by the artist LeRoy Neiman - best known for his expressionist renderings of sporting events.
The top lot is undoubtedly a painting of Marilyn Monroe on a baseball signed by Joe DiMaggio, an exceptionally rare lot given the legendary centre-fielder's reluctance to speak about his relationship with the star.
It is expected to sell for in excess of $6,000.
Ivy commented: "In the two years since his passing at age 91, LeRoy Neiman has seen a significant surge in his already red-hot collecting market".
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